How to deploy a contract to testnet?

Question

I have been testing and a lot of the docs refer to deploying to a local node only. How we can deploy a contract to the jungle testnet?

Answer 1

Here's an example of how to deploy to a testnet (assuming you've already set up the wallet and accounts). In this example we'll deploy the hello contract to the helloworld54 account on the CryptoKylin testnet:

cd hello/

touch hello.cpp 

eosiocpp -o hello.wasm hello.cpp
eosiocpp -g hello.abi hello.cpp

cd ..

# deploy
cleos -u http://api.kylin.alohaeos.com set contract helloworld54 hello/ -p helloworld54@active

# call contract action
cleos -u http://api.kylin.alohaeos.com push action helloworld54 hi '["bob"]' -p helloworld54@active
# >> Hello, bob 

hello.cpp

#include <eosiolib/eosio.hpp>
#include <eosiolib/print.hpp>
using namespace eosio;

class hello : public eosio::contract {
  public:
      using contract::contract;

      /// @abi action
      void hi( account_name user ) {
         print( "Hello, ", name{user} );
      }
};

EOSIO_ABI( hello, (hi) )

Some things to note:

You have to create a new account for every new contract that you deploy. An account can have 0 or 1 contracts. To create an account you have to stake at least 1 EOS. You can use the testnet faucet to get free EOS.

Answer 2

If you've been using cleos in the docs, cleos uses the -u or --url switch to specify the endpoint used to interact with when deploying or interacting with a contract.

Instead of referencing a local node like -u http://localhost:8888 you can instead reference a Jungle Net endpoint or even main net endpoint when trying to interact with a different chain.

Keep in mind you'll require an account on each of these chains and keys imported for cleos to work OK.

Answer 3

When using cleos use - u with the url of the test net